Drill and tube arrangement with knock-of drill portion



INVENTOR @e/JZUZJJp/U B. K. B. JANSSON Filed Aug. 3, 1965 DRILL AND TUBEARRANGEMENT WITH KNOCK-OFF DRILL PORTION Feb. 27, 1968 United StatesPatent lice 3,379,558 Patented Feb. 27, 1968 s,37a,65s DRILL AND TUBEARRANGEMENT WITH KNCK-FF DRILL PORTKN Eengt K. B. Jansson,Faltiagarvagen 34 A, Skelleftea, Sweden Filed Aug. 3, 1965, Ser. No.476,834 Claims priority, application Sweden, Aug. 11, 1964, 9,691/64 13Claims. (Cl. 175-215) ABSTRACT OF THE DISCLSURE A drill is provided, fordrilling substantially elongated cylindrical holes in the earth and likesubstances, comprising a drill rod having a drill head portion and adrill crown portion, both the head portion and the crown portions havingcutting edges. A tube is provided, disposed about the drill rod, thetube being longitudinally movable a predetermined distance along thedrill rod, and being adapted to knock the drill crown portion off thedrill head portion, when the drilling operation is completed, by pullingthe drill rod and drill head out of the drilled hole. Rinsing means areprovided whereby fluid may be delivered to the drill head and extractedthrough the tube.

The present invention relates to a drill and more especially to a drillfor drilling in earth or loose species of stone, e.g` for performingso-called grouting, the drill rod being surrounded by a tube.

Grouting in the pressing of that tightening or reinforcing material,such as cement or concrete blends, into holes and cracks in rocks andearth.

The known drills of the indicated type have a drawback in that thedrills and the tubes are very likely to stick in the hole being drilledbecause of earth materials which have been worked loose by the boring ordrilling action. Bad diiculties also occurring when the drill and thetube are removed from the hole after a iinished drilling action.

When using known drills it has been necessary to withdraw the drill aswell as the tube after the completed drilling operation and to insert,instead, another tube through which the grouting material shall beintroduced and pressed into the earth. However, the introduction of thisfinal tube is often extremely difficult or quite irnpossible due to thecircumstance that the rock or the earth material is falling down or isbeing cracked, thus preventing the introduction of the tube. A drawbackis also that the iinal tube must have a relatively small diameter.

An object of the present invention is to eliminate the above indicateddrawbacks and to provide a drill through 'r which the earth materialworked loose by the drilling action will be positively removed, wherebythe drill will be completely free from any tendency to stick in thehole, and through which the introduction of the second or final tube ispossible in connection with the drilling operation itself. The saidiinal tube may, due to the removal of the earth material, have a maximumdiameter, that is a diameter which is approximately the same as thediameter of the drilled hole.

These objects of the invention are made possible through the fact thatthe tube, preferably at or near its leading end adjacent to the drillhead, is provided with openings through which rinsing water supplied tothe drill head will be conducted into the tube, the outer or rear end ofwhich is provided with an outlet for the rinsing water.

According to the invention the tube surrounds a portion of the drillhead which is provided with external recesses, preferably longitudinalgrooves 0r canals, for the rinsing liquid, and the tube is mounted witha considerable play in the longitudinal direction of the drill.

t has been proven that the drill according to the present inventionneeds only very reasonable impact impulses in order to be able to followthe drill crown in the hole being actually drilled. Trials have alsoproved that there is absolutely no blocking of either the drill or thetube even in spite of the most brittle rocks or smeary earths.

The maximum effective diameter of the drill is determined through adrill crown mounted on a conical portion of the drill head. This drillcrown shall be knocked olf the drill head by means of the inner orforward end of the tube when the drill rod and the drill head are pulledout of the drilled hole.

Because thus the drill crown 0r at least some portion of the drill crownwill be left in the hole, drill bits of hard metal or any otherexpensive material may be dimensioned rather sparingly in order to savecosts for such material. The driving impacts against the tube may beperformed by a drilling machine adapter which is arranged to transmitimpact impulses for a drilling machine not only to the drill or thedrill rod but also to the tube. A special member may transmit the impactimpulses from the adapter to the tube.

In the drawing:

FlGURES l and 2 are longitudinal views with major portions illustratedin section of the lower and upper halves of the drill of this invention,respectively, broken along the line A-A of the figures.

The invention will now be declared more in detail, reference being hadto the accompanying drawing which shows an embodiment presented as anon-limiting example.

The said embodiment comprises a drill head 1, which may comprise ofseveral parts 2 and 3 coupled together by means of a coupling sleeve 4,and a drilling machine adapter 5 mountable on the rear, speciallythreaded end of the drill or rod.

The drill head 1 has a central portion 6 provided with drill bits and aconical or tapered portion '7 situated at the rear of the said centralportion in respect to the driling direction. Upon this conical portionwhich has a relatively small cone angle or taper angle, e.g. only 15, ismounted a drill crown S which is correspondingly conical and has acircumferential character.

The connection of the drill head ll to the drill rod 2 as well as theconnection between the drill rod parts 2 and 3 with the connectingsleeve 4 may have a special thread which also forms the connectionbetween the rear end of the drill rod 3 .and the adapter 5.

The drill rod 2, 3, 4 is surrounded by a t-ube 9 which is to beintroduced into the drill hole, and which has an outer diameter which issubstantially equal to or slightly less than the maximum effectivediameter of the drill, such maximum diameter being determined by thedrill crown 8.

The tube 9 is guided in co-axial relation to the drill crown and thedrill rod 2, 3 by means of a cylindrical surface 1a on the drill head 1and a boring 10 in a member 11 between the adapter 5 and the tube 9. Thesaid boring lil is co-axial with the drill rod part 33. The member 11transmits the impacts received from drilling machine (not shown) to theadapter 5 to the tube 9. Through the impacts transmitted by the member11 the tube 9 will be forced to follow the drill head 1 and the drillingportions 6 and 8 of the drill head in a most positive way.

The play of the tube 9 relative to the surface 1a of the drill head 1and the surface of the preferably internal boring or socket of themember 11 may be only about one or a few millimeters in radialdirection. This play is clearly indicated in the drawing. However theplay of the tube in axial direction ispreferably quite considerable.

The drill crown 8 shall be knocked oif, after a completed drillingoperation by the inner end of tube 9 when the drill rod and the drillhead are being pulled out of the drilled hole the tube 9 likewiseremaining in this hole. Because the drill crown 8 is thus to bediscarded the same should not, of economical reasons be provided withgreater or more expensive bits than what is to be consumed in theindividual drilling operations. The central drill portion 6 may however,be stronger since the same should be used several times.

Instead of two separate drill crowns, namely the central drill portion 6and the circumferential or ring-shaped drill crown 8, it is possible touse only one single drill crown mounted upon the conical or taperedportion 7.

12 designates a hole drilled in the member 11, through which a key maybe introduced into engagement with surfaces 13 on the drill rod part 3when the adapter 5 shall be mounted lupon the rod 3 or removedtherefrom.

14 designates a rinsing canal arranged in an old manner in the drill rodand leading centrally outof the drill portion 6, and the tapered portion7 of the drill head is provided with radial rinsing canals 15 and with a.ring groove 16, through which canals and through which groove rinsingliquid may be supplied to and through the canals 17 in the drill crown 8into the drilled hole.

In accordance with the present arrangement the front end of the tube 9in respect of the drilling direction is provided with recesses oropenings 18 through which the rinsing liquid together with loose-drilledrock and earth materialwill pass to one or more longitudinal grooves 19provided in the mantle surface of the drill head 1. The rinsing orflushing liquid together with the said loosedrilled material isthereupon passing freely through the tube 9 to a boring arranged in themember 11 and comi Y municating with the guiding boring 10. An outlet 21is leading out of the boring 20.

The above mentioned rinsing away of the loose-worked material throughthe tube involves an astonishingly great and deciding improvement. Thus,neither the drill itself nor the tube shows any longer the slightesttendency of sticking in the drilled hole. This is due to the fact thatdrilling is always performed completely freely and without anyobstructions in a very clean hole. Not even in clay-type or loamy earthsthere are any longer any diiculties. It follows that it is possible toobtain drill holes of a length of 150 metres and more. To this favorableresult the rather big axial play of the tube is contributing as well asthe influence of the adapter upon the tube.

The rinsing away of the loose-worked material and the knocking off ofthe drill crown S after completed drilling operation are thus, incombination, giving a very good drilling speed and eliminating alldifficulties when the drill rod shall be removed out of the drilledhole, since the tube 9 simply remains in the hole.

When drilling long holes the drill rod may in a known manner be extendedunlimitedly.V Then also the tube 9 is extensible correspondingly, sincethe tube may be eX- tended or made longer by means of special extensionparts and coupling members or perhaps through welding or brazing asindicated at 22.

The drill according to the invention functions very well also with thelongest drill rods and tubes, respectively, and the outer diameter ofthe tube 9 may be approximately the same as the maximum eifectivediameter of the drill crown or the diameter of the drill hole withoutany sticking.

In the known drills, as indicated in the opening part of thisdescription, the diameter of the final tube must be considerably smallerthan the diameter of the drill hole. Because in the drill according tothe invention the tube 9 may have approximately the same diameter as thehole, it is possible, when using the drill according to the invention,to drill holes with a considerably smaller driameter than it washeretofore for the nal tube diameter. This involves an enormously greatsaving, since every possible reduction of the hole diameter means aconsiderably increased drilling speed and less consumption of expensivedrilling material.

The invention makes it possible to drill the hole and to introduce thenal tube into this hole in one and the same operation.

The invention is not limited only to the embodiment here described andshown, since other embodiments are possible within the scope of theinvention.

It is possible to construct the drilling machine adapter with a guidefor the tube 9, whereby the member 11 may tbe dispensed with, i.e. it ispossible to combine the parts 5 and 11. Y

In the embodiment shown it is assumed that impact or percussion drillingis concerned. It is however to be seen that the invention is applicablealso for drills which are not impact drills.

A great advantage of the invention consists in that the tube 9, due tothe near correspondence between its outer diameter and the diameter ofthe drilled hole, already relatively soon after a nished drilling willstick surprising steady in the drilled hole and also tighten wellagainst the walls of the hole, which circumstance very positivelycontributes to the good result when grouting rocks and earths. There is,however, no risk that the tube will stick during the drilling operationor even under short stops, e.g. for performing the necessaryextensions'of the drill i rod and the tube.

Through the member 11 the impact impulses of the impact piston of thedrilling machine are transmitted to the drill rod `in a most positivemanner, since the member 1lV oscillating between the adapter 5 and thetube 9 consumes only a relatively small part of the impact energy. Themember 11 shall together with the tube 9 have aconsiderable axial playor movement which, however, must be less than the length of the boring10 guiding the tube 9. A suflicient play must of course be presentbetween the drill rod and the member 11 so that this member may be ableto move easily in the axial direction.

What I claim is:

1. A drill adapted for drilling in earth or loose rocks and species ofstone, in order to perform grouting, in which the rod of the drill issurrounded by a tube and includes a drill head at one end thereof,characterized in that the tube is provided at its lower end adjacent tothe drill head with openings through which rinsing water supplied to thedrill head will be conducted into the tube, the tube also being providedwith an outlet for the rinsing water at its upper end, wherein the tubehas a considerable play in the longitudinal direction of the drill inwhich a drilling machine adapter is disposed on the upper end of thedrill rod, said adaptor being operable to transmit impact impulses froma percussion drilling machine to the drill rod and to the tube.

2. A drill as claimed in claim 1, in which a special member is adaptedto transmit the impact impulses from the adapter to the tube, saidspecial member including guide means for holding the tube in co-axialalignment with the drill rod, said special member being provided with arinsing water outlet which communicates with the guide 5. A drill asclaimed in claim 4, in which the effective diameter of the drill isdetermined by a drill crown mounted on a conical or tapered portion ofthe drill head, characterized in that the drill crown is capable ofbeing knocked olf the inner or forward end of the tube after a completeddrilling operation by pulling the drill rod and the drill head out ofthe drilled hole.

6. A drill adapted for drilling in earth or loose rocks and species ofstone, in order to perform grouting, in which the rod of the drill issurrounded by a tube and includes a drill head at one end thereof,characterized in that the tube is provided at its lower end adjacent tothe drill head with openings through which rinsing water supplied to thedrill head will be conducted into the tube, the tube also being providedwith an outlet for the rinsing water at its upper end, in which theeffective diameter of the drill is determined by a drill crown mountedon a conical or tapered portion of the drill head, characterized in thatthe drill crown is capable of being knocked off the inner or forward endof the head after a completed drilling operation by pulling the drillrod and the drill head out of the drilled hole.

7. A drill as claimed in claim 3, in which the longitudinal or axialplay of the tube allows the member to oscillate between the adapter andthe tube and thereby impart axial movements to the tube.

8. A drill as claimed in claim 2, in which the preferably cylindricalportion of the drill head, which is surrounded by the corresponding endof the tube, is adapted to guide the tube ends co-axially relative tothe drill rod, the drill head and the drill crown.

9. A drill as claimed in claim 2, in which the edective diameter of thedrill is determined `by a drill crown mounted on a conical or taperedportion of the drill head, characterized in that the drill crown iscapable of being knocked off the inner or forward end of the tube aftera completed drilling operation by pulling the drill rod and the drillhead Out of the drilled hole.

10. A drill adapted for drilling in earth or loose rocks and species ofstone, in order to perform grouting, in which the rod of the drill issurrounded by a 'tube and includes a drill head at one end thereof,characterized in that the tube is provided at its lower end adjacent tothe drill head with openings through which rinsing water applied to thedrill head will be conducted into the tube, the tube also being providedwith an outlet for the rinsing water at its upper end, wherein the tubesurrounds a portion of the drill head which is provided with externalrecesses, in the form of longitudinal channels for the rinsing liquid,in which the effective diameter of the drill is `determined by a drillcrown mounted on a conical or tapered portion of the drill head,characterized in that the drill crown is capable of being knocked ot theinner or forward end of the head after a completed drilling operation bypulling the drill rod and the drill head out of the drilled hole.

11. A drill adapted for drilling in earth or loose rocks 5 which the rodof the drill is surrounded by a tube and includes a drill head at oneend thereof, characterized in that the tube is provided at its lower endadjacent to the drill head with openings through which rinsing watersupplied to the drill head will be conducted into the tube, the tubealso being provided with an outlet for the rinsing water at its upperend, wherein the tube has a considerable play in the longitudinaldirection of the drill, in which the effective diameter of the drill isdetermined by a drill crown mounted on a conical or tapered portion ofthe drill head, characterized in that the drill crown is capable ofbeing knocked off the inner or forward end of the head after a completeddrilling operation by pulling the drill rod and the drill head out ofthe drilled hole.

12. A drill adapted for drilling in earth or loose rocks and species ofstone, in order to perform grouting, in which the rod of the drill issurrounded by a tube and includes a drill head at one end thereof,characterized in that the tube is provided at its lower end adjacent tothe drill head with openings through which rinsing water supplied to thedrill head will be conducted into the tube, the tube also being providedwith an outlet for the rinsing water at its upper end, wherein the drillhead includes a cylindrical portion which is surrounded by thecorresponding end of the tube, and is adapted to guide the tube endco-axially relative to the drill rod, the drill head and a drill crownwhich is disposed on the drill head, in which the effective diameter ofthe drill is determined by the drill crown mounted on a conical ortapered portion of the drill head, characterized in that the drill crownis capable of being knocked oif the inner or forward end of the headafter a completed drilling operation by pulling the drill rod and thedrill head out of the drilled hole.

i3. A drill adapted for -drilling in earth and the like substances,comprising a rod, a drill head attached to said rod, a drill crownmounted on said drill head on a tapered portion thereof, and a tubedisposed about said rod; the elfective diameter of the drill beingdetermined by the diameter of the drill crown; the tube comprising meansfor knocking the drill crown olf the head after a completed drillingoperation when the drill rod and drill head are pulled out of thedrilled hole.

References Cited UNITED STATES PATENTS 1,295,969 3/1919 Carmichael175-215 X 2,023,966 12/1935 Montee 175-207 X 2,121,858 6/1938 Chew175-214 X 2,588,068 3/1952 Williams 175-207 X 2,914,306 1l/l959 Failing175-213 X 3,022,840 2/1962 Hobos 175-213 X 3,227,230 l/l966 Lagerstrom175-214 CHARLES E. OCONNELL, Primary Examiner.

NILES C. BYERS, IR., Examinez'.

